Treatment of hydrocarbon oils



INVENTOl-' JEAN DELATTRE sEGUY July 25, 1939 J. D. sEGUY TREATMENT 0FHYDROGARBON OILS Original Filed July 28, 1930 Patented July 25, 1939UNITED STATES PATENT OFFICE TREATBIENT OF HYDROCARBON OILS WalleVApplication July 28, 1930, Serial No. 471,206 Renewed May 4, 1938 5Claims.

This invention contemplates an improved process for the treatment ofhydrocarbon oils, particularly for the conversion of so-called heavy orhigh boiling hydrocarbon oils into lower boiling hydrocarbon oils.

The invention provides a process in which hydrocarbon oils are subjectedto cracking conditions and the vapors and unvaporized liquid areseparately treated.

In one specific aspect the process comprises subjecting the oil to aliquid-vapor phase cracking treatment under heat and pressure,discharging the hydrocarbon material at conversion temperature into avaporizing zone at substantially lower pressure, separating thevaporized and unvaporized products therein, subjecting the vapors to adephlegmating or iractionating action, segregating during the processheavier and lighter reflux condensates, separately returning saidheavier and lighter condensates to separate heating elements where theyare treated under vapor phase conditions, separating the lower boilingcomponents of the vapors from the fractionating zone, and cooling,condensing and collecting the lower boiling distillate product of theprocess.

My process also provides an operation wherein the oil being treated maybe reduced to coke and distillate containing the low boiling products ofthe process.

My invention further provides a process for the production of highanti-knock gasoline.

The invention will be more fully described by reference to theaccompanying diagrammatic drawing, which is not to scale, and whichillustrates one form of apparatus suitable for carrying out the processof the invention.

The raw oil charging stock for the process may be fed through line I,valve 2, pump 3, valve 4, line 5 and heat exchanger 6 which permitsindirect heat exchange between the incoming raw oil and the vapors inthe fractionating zone, causing a partial condensation of said vapors,the resulting reilux condensate being returned as hereinafter described.The oil leaving the indirect heat exchanger 6 passes through line l,valve 8, line 9, and valve I into heating element I I located in anysuitable furnace setting I2. A portion or all of the raw oil may bepassed directly through line I3 controlled by valve I4 into line 9 andthrough the heating element II. The oil after being raised to conversiontemperature passes through the transfer line I5 controlled by valve I6into the ilashing and vaporizing zone I'I which is under a substantiallyreduced pressure with respect to the heating element I I.

The unvaporized liquid residue when formed is withdrawn through line I8controlled by valve I9. The vapors resulting from the flashing operationpass through riser into compartment 2| of the fractionating column 22.The reflux condensate which collects upon the deck or plate 23 in thefractionating column 22 may be withdrawn through line 24 controlled byvalve 25 and pumped by means of pump 26 through line 21 and valve 28into the vapor phase heating element 29 located in any suitable furnacesetting 30. The highly heated vapors are discharged through line 3l andvalve 32 back into the flashing and vaporizing zone II. Similarly, thevapors leaving compartment 2l pass through riser 33 into compartment 34of the fractionating column 22 and the reflux condensate formed thereinand collected on deck or plate 35 is returned through line 36 and Valve3l and pumped by means of pump 38 through line 39 and valve 4D throughvapor phase heating element 4I located in any suitable furnace setting42. The highly heated vapors from this vapor phase heating Zone aredischarged through line 43 controlled by valve 44 into the flashing andVaporizing zone I'I.

It is quite apparent that the relative proportions of reflux condensateand the temperature to which same is heated permit complete vaporizationin flashing or vaporizing zone Il even to the extent of reducing theunvaporized residue therein to coke, and this is one of the features ofmy invention.

It is also apparent that the reflux condensate collecting on deck orplate 23 is heavier and higher boiling in characteristics than thatcollected on deck or plate 35 and that the conditions for reconversionin heating elements 29 and 4I are regulated accordingly.

The vapors containing the low boiling product of the process leavingfractionating column 22 pass through vapor line 45 controlled by valve46 and through line 4l into cooler and condenser 48, the distillatetogether with the gases passing through line 49 controlled by valve 59into receiver 5I. The distillate in receiver 5I may be removed throughline 52 controlled by valve 53. The gases in receiver 5I may bedischarged through line 54 controlled by valve 55. A portion of thedistillate may be returned to the fractionating column for coolingpurposes to control the character of the distillate through line 56controlled by valve 5l by means of pump 58 and through line 59.

A portion of the raw oil may be diverted from line 9 through line 63 andmay be fed through line 62 and valve 66 into line I5 to mix with andcool the converted material from heating element il. Similarly a portionof the raw oil may be fed into line 133 through line 6l controlled byvalve 65 to cool the products from heating element lil. Raw oil fromline 63 may also be utilized to cool the heated products from heatingelement 29 by introducing a portion of the raw oil through line 60controlled by valve 64 into line 3l.

As examples of the operating conditions and yields of products obtainedby the process of my invention a 27 gravity A. P. I. Mid-Continenttopped crude was treated, the temperature in heating element El beingapproximately 900 degrees F. The pressure upon this heating element wasapproximately 200 pounds per square inch. The heavier reflux condensatefrom deck or plate 23 was heated in coil 29 to a temperature ofapproximately 980 degrees F. The lighter reflux from deck or plate 35was heated in coil fil to a temperature of approximately 1050 degrees F.The pressures upon the heating elements 29 and ll were approximately 150pounds per square inch. During this operation the residue in flashing orevaporating zone ll was reduced to coke. Approximately 55 per cent ofgasoline having an anti-knock value of approximately 60 per cent benzolequivalent was produced, that is, equivalent in anti-knock value to amixture of Pennsylvania straight run gasoline and benzol, containing 60per cent of the latter. Approximately 60 pounds of coke per barrel ofraw oil charged was made at the same time. The yield of gas wasapproximately 800 cubic feet per barrel of oil charged. Approximately l0per cent of pressure distillate bottoms was formed during the operation.

By reducing the temperatures in the vapor phase heating elements, theproduction of gas was reduced somewhat but the anti-knock value was alsolowered. Operating the heating elements "il and 29 at substantiallyequalized pressure with the flashing Zone l1 at approximately 25 poundsper square inch pressure during this operation, increased the yield ofgas somewhat over a similar operation where the same temperatureconditions but higher pressure prevailed in the heating elements. Otherchargng stock, both .lighter and heavier than that given in the aboveexample, gave parallel results, the lighter charging stock producinglarger yields of gasoline and less coke, the heavier vice versa.

Generally speaking, the temperatures which I may employ in heatingelement Il will vary between 800 degrees F. and 950 degrees F.; that is,those temperatures usually employed in liquidvapor phase operation andthe temperature in heating elements 29 and 4| will vary between 950degrees F. and 1250 degrees F., more or less. Higher tempertaures willtend to produce an excessive gas formation, but the process is adaptedto gas making and may be so used if desired, although I prefer to adaptit to the production of a high anti-knock gasoline. By introducing aportion of the raw oil charging stock into the transfer or dischargelines from heating elements 2S and 4l I found that I may substantiallyreduce the formation of gas especially when high temperatures areemployed in these heating elements, as in this manner the heatedproducts may be cooled before sufficient reaction time has been allowedfor the excessive formation of gas and coke.

I claim as my invention:

l. The method of decomposing hydrocarbon oils to form low boilingproducts therefrom which comprises maintaining residual oil products ina decomposing zone at a tempertaure to effect decomposition thereof intocoke substantially free from liquid products, removing vapors from saiddecomposing Zone and supplying fresh oil containing residual productsinto contact with the removed vapors, thereby vaporizing a portion ofsaid fresh oil and heating the unvaporized residual constituentsthereof, discharging said unvaporized residual constituents, free fromthe vaf the fresh oil before it is supplied into contact with the vaporsfrom said decomposing zone, and heating a heavier one of saidcondensates to cracking temperature and discharging it into thedecomposing zone to maintain a decomposing temperature therein andconvert the residual products into coke substantially free from liquidproducts.

2. The method of decomposing hydrocarbon oils to form low boilingproducts therefrom which comprises maintaining residual oil products ina decomposing zone at a temperature to effect decomposition thereof,removing vapors from said decomposing zone and supplying fresh oilcontaining residual products into contact with the removed vapors,thereby vaporizing a portion of 3 said fresh oil and heating theunvaporized residual constituents thereof, discharging said unvaporizedresidual constituents, free from the vaporized portion, into said zoneto be decomposed therein, cooling the combined vapors from said Zone andfrom the fresh oil to condense therefrom a plurality of fractions ofdifferent intermediate boiling point ranges, separately collecting theresulting condensates, heating a lighter condensate thus separated tovaporizing and cracking temperature under pressure to effect conversionthereof, commingling vapor products of said cracking with the fresh oilwhile the latter is substantially below its vaporizing temperature andbefore it is supplied into contact with the vapors from said decomposingZone, and heating a heavier one of said condensates to crackingtemperature and discharging it into the decomposing zone to maintain adecomposing temperature therein.

3. A hydrocarbon oil conversion process which comprises maintainingresidual oil products at decomposition temperature in the lower portionof an enlarged chamber, supplying fresh oil containing residual productsto the vapor space of said chamber and into Contact with vapors therein,a portion of the fresh oil being thereby vapor-- ized in said vaporspace and the unvaporized portion thereof descending into said lowerportion of the chamber, removing vapors from said chamber andfractionating the same to separate a plurality of reflux condensatestherefrom, heating a lighter reflux condensate thus separated tovaporizing and cracking temperature under pressure to effect conversionthereof, commingling vapor products of said cracking with the fresh oilwhile the latter is substantially below its vaporizing temperature andbefore it is contacted with the first-mentioned vapors in the vaporspace of said chamber, and heating a heavier one of said reuXcondensates to cracking temperature and discharging it into said chamberbelow the point of introduction of the fresh oil to maintain adecomposing temperature therein.

4. The process as dened in claim 3 further characterized in thatresidual products are reduced to coke in said chamber.

5. A hydrocarbon oil conversion process which comprises maintainingresidual oil products at decomposition temperature in the lower portionof an enlarged chamber, supplying fresh oil containing residual productsto the vapor space of said chamber and into contact with vapors therein,a portion of the fresh oil being thereby vaporized in said vapor spaceand the unvaporized portion thereof descending into said lower portionof the chamber, removing vapors from said chamber and fractionating thesame to separate a plurality of reuX condensates therefrom, heating oneof the reflux condensates thus separated to vaporizing and crackingtemperature under pressure to effect conversion thereof, comminglingVapor products of said cracking with the fresh oil while the latter issubstantially below its Vaporizing temperature and before it iscontacted with the first-mentioned vapors in the vapor space of saidchamber, and heating another cf said reux condensates to crackingtemperature and discharging it into said chamber below the point ofintroduction of the fresh oil to maintain a decomposing temperaturetherein.

JEAN DELATTRE SEGUY.

